Prompt drug delivery of rabeprazole through raft formation: In vitro and in vivo evaluation

Abstract Rabeprazole is degraded in the stomach below 2.5 pH and the raft forming system keeps the stomach pH above 3.5. Above pH 3.5, rabeprazole is not degraded in the stomach. The present study aimed to maintain the stomach pH above 3.5 for an appropriate period of time and improve the bioavailability of rabeprazole. The rabeprazole, polymers and raft, were characterized by FTIR, XRD, TGA and DSC. The RR5 formulation showed a release of 99.93 % rabeprazole at 20 min in simulated gastric fluid (SGF). FTIR analysis showed the compatibility of drug and excipients. The DSC thermogram indicated the endothermic peak of rabeprazole at 179 oC. The RR5 formulation and Repit® 20 mg capsule was selected as the test and reference formulations respectively for pharmacokinetic study. Healthy albino rats were divided into two groups (reference and test) each having 6 rats and blood samples were collected for 24 h. The Cmax and tmax for the reference and test formulations were 465±0.237 ng/mL and 4±1.398 h and 495±0.097 ng/mL and 2±0.025 h, respectively. AUC0-t of the reference and test formulations was 3316.75±3.418 ng/mL.h and 4910.25±3.467 ng/mL.h, respectively. Our study proves the potential effectiveness of rafts for the fast oral delivery of rabeprazole.